Licensed wireless systems provide mobile wireless communications to individuals using wireless transceivers. Licensed wireless systems refer to public cellular telephone systems and/or Personal Communication Services (PCS) telephone systems. Wireless transceivers include cellular telephones, PCS telephones, wireless-enabled personal digital assistants, wireless modems, and the like.
Licensed wireless systems utilize wireless signal frequencies that are licensed from governments. Large fees are paid for access to these frequencies. Expensive base station (BS) equipment is used to support communications on licensed frequencies. Base stations are typically installed approximately a mile apart from one another (e.g., cellular towers in a cellular network). The wireless transport mechanisms and frequencies employed by typical licensed wireless systems limit both data transfer rates and range. As a result, the quality of service (voice quality and speed of data transfer) in licensed wireless systems is considerably inferior to the quality of service afforded by landline (wired) connections. Thus, the user of a licensed wireless system pays relatively high fees for relatively low quality service.
Landline (wired) connections are extensively deployed and generally perform at a lower cost with higher quality voice and higher speed data services. The problem with landline connections is that they constrain the mobility of a user. Traditionally, a physical connection to the landline was required.
In the past few years, the use of unlicensed wireless communication systems to facilitate mobile access to landline-based networks has seen rapid growth. For example, such unlicensed wireless systems may support wireless communication based on the IEEE 802.11a, b or g standards (WiFi), or the Bluetooth® standard. The mobility range associated with such systems is typically on the order of 100 meters or less. A typical unlicensed wireless communication system includes a base station comprising a wireless access point (AP) with a physical connection (e.g., coaxial, twisted pair, or optical cable) to a landline-based network. The AP has a RF transceiver to facilitate communication with a wireless handset that is operative within a modest distance of the AP, wherein the data transport rates supported by the WiFi and Bluetooth® standards are much higher than those supported by the aforementioned licensed wireless systems. Thus, this option provides higher quality services at a lower cost, but the services only extend a modest distance from the base station.
However, such unlicensed wireless communication systems require modified or dual-mode user equipment in order to allow seamless communications across both the unlicensed wireless system and the licensed system. Therefore, there is need to provide the low cost and quality of service benefits of the unlicensed wireless system without requiring change to the user equipment. As a result, technology is being developed to integrate short-range licensed wireless base stations that emulate components of the licensed wireless system and the licensed wireless system in a seamless fashion. Such seamless integration should enable a user to access, via a single handset (i.e., user equipment), the short-range licensed wireless system (i.e., femtocell system) when within the range of such a system, while accessing a licensed wireless system when out of range of the short-range licensed wireless system.
To perform such integration requires sharing of limited licensed wireless system resources and some various messaging functions needed to communicate with the licensed wireless system. Therefore, a solution is needed to overcome the limited availability of resources. Additionally, such a solution should be implemented without changing either the user equipment used to access the network or components of the network itself in order to provide a fully transparent integrated communication system.